Calls for an arrest and charges in a Rutland hit-and-run that killed a Mendon woman continue to be heard on the city’s streets and in social media forums six days after former city attorney Christopher Sullivan told police he was the driver in the crash.

But a Vermont State Police crash reconstructionist and a former state prosecutor said this week that delays in cases like the one that killed 71-year-old Jane Outslay aren’t unusual as police and prosecutors try to gather all the evidence they need to build a strong case.

“It’s not uncommon,” said Robert Sand, former Windsor County state’s attorney. “The last thing you want to do is prematurely file a case.”

Such a view is contrary to the opinions of many in the Rutland community who have taken to Facebook in the days since Sullivan identified himself as the driver in the crash and surrendered the 2004 Lexus sedan he was driving at the time.

Many members of the community, including Emma Martens who came to a press conference at the police department Friday to ask pointed questions, believe Sullivan is receiving special treatment because he hasn’t been arrested, charged or imprisoned and remains free with no restrictions on his travel or other activities.

A short update about the continuing investigation that was posted on the Rutland Herald Facebook page at 9 a.m. Tuesday garnered 70 comments by 6 p.m. — most from posters frustrated by the lack of criminal charges in the case.

“This man should certainly face charges,” Proctor schoolteacher Chuck Laramie wrote Tuesday on Facebook. “To say that (Sullivan) due to his presumed status is not getting special treatment would be ludicrous. Leaving the scene of an accident is a crime, for that he should at least be charged and arraigned.”

Leaving the scene of a crash is a criminal charge in Vermont. For crashes involving property damage, it’s a misdemeanor offense. But fatal hit-and-runs can result in a felony charge and up to 15 years in jail if convicted.

Rutland City Police and prosecutors with the Vermont attorney general’s office, who took over the case at the request of the Rutland County state’s attorney’s office, have declined to comment on any specifics driving the investigation. But Police Chief James Baker on Friday emphatically denied any special treatment for Sullivan.

“For anyone to think that we are treating Mr. Sullivan differently than anyone else is ludicrous,” Baker said Friday.

“We cannot take liberties away until we have the case and the evidence exactly right. We have to deal with facts, not rumors,” the chief added.

Outslay’s family members said Tuesday they weren’t worried about the progress of the case.

“I’m not getting frustrated,” Outslay’s husband, Merrill Outslay said. “I recognize they have to do their job.”

Outslay’s son, Gregor Outslay, said Tuesday the family has been more focused on laying his mother to rest than on Sullivan.

“On our side of things there’s no anxiety,” he said. “We’re focused on the funeral and the wake and haven’t put that much energy and thought into the criminal case.”

He added that Rutland Police have kept the family informed and have been supportive during the investigation.

While some onlookers suspect ulterior motives for delays in making an arrest and bringing charges in the case, Sand said the reality in most cases like the one in Rutland is far more practical.

Sand, who now works for the Shumlin administration and has no involvement in the investigation, said he couldn’t say for sure what factors are influencing the case in Rutland. But he said from his experience as a prosecutor, taking the time to build a strong case and match it with the most applicable criminal offense is a top consideration.

There are a range of criminal offenses that could apply to a hit-and-run crash, each requiring a different threshold of conduct and evidence to prove.

“Unless there’s a public safety risk or a risk of flight, delaying and letting investigators build their case is the most prudent thing to do,” he said. “A careful review of the facts is exactly what the public should want the police and prosecutors to do before making charging decisions.”

Examining evidence in hit-and-run cases can take a lot of time as investigators work backward to recreate elements that existed at the moment of a crash, according to Vermont State Police Sgt. Garry Scott.

Scott, the commander of the state police crash reconstruction team, said determining critical elements such as the vehicle’s speed can take time as investigators rely on a number of sources, including road marks, autopsy results and data stored in the computer system controlling a vehicle’s airbag system to come up with an exact rate of speed.

Scott added that it can be misleading to judge a vehicle’s speed based on the distance a pedestrian was moved after being struck by a vehicle.

At low speeds, he said, a pedestrian could be carried long distances on the hood and windshield. High-speed impacts are more likely to leave pedestrians at the point of impact as they are often thrown straight up into the air by a vehicle.

Careful analysis of forensic evidence is even important in cases where a confession has been made, Scott said, because sometimes the evidence shows that someone else was behind the wheel of a vehicle.

To determine who was driving in a crash, investigator often look for injuries from seat belts or the deployment of airbags and interviews are conducted with other passengers in the vehicle and anyone else who might have seen who was behind the wheel prior to a crash.

“You want to tie everything together,” Scott said. “If you bring a bad charge early, it taints everything that happens in a case further on.”